汽油饱和蒸汽压对极低温下自然吸气发动机冷起动特性影响分析

In order to research the influence of different gasoline saturated vapor pressure on the cold start performance of naturally aspirated engine, gasoline with saturated vapor pressure of 6.5psi, 8.7psi and 12.0psi was selected, and the cold start test was carried out by using vehicle equipped with 1.5L naturally aspirated engine, the test temperature was - 30 ℃ and - 20 ℃. the results show that the start time, overshoot and number of speed drops decrease with the increase of gasoline saturated vapor pressure, the gasoline with higher saturated vapor pressure is helpful to the start performance of vehicles in low temperature area regions.